Sheet feeders for printers are well known in the art and, as an example thereof, reference is made to our earlier Application Ser. No. 321,419 filed Nov. 16, 1981, now U.S. Pat. No. 4,456,240. In this known sheet feeder, sheets of paper are fed from a tray to a printer and the printed sheets are stacked at a stacking station in the order in which the sheets are printed. In this arrangement, the sheets are fed with their printed surfaces facing the next successive sheet and in order to collate the sheets for a document or letter, it is necessary for the user to rearrange the sheets. This is a relatively tedious operation particularly where the number of printed sheets becomes substantial.
In a sheet feeder where a plurality of different types of sheets are assembled in combination with an envelope, it is especially difficult to rearrange the sheets and the envelope to prepare a given item of correspondence in readiness for mailing or assembly.
Furthermore, in the conventional sheet and envelope feeders, the sheets and envelopes are driven from each of the trays by a feed roller which, in turn, is driven from the printer platen through a combination lock gear assembly. This is slow, noisy and mechanically unreliable.